What if the same code used for FY2016 & FY2017

For this lesson specifically, when you look up the value of the code, you started with the earlier year and would look up in a later year only if the code does not exist for the earlier year. However, I am sure that the later years (for example FY2017) have the same code (ex.2001190000111111) from the previous year (FY2016). What I meant is 2001190000111111 exists in all three sheets and has different content (capital cost vs. other revenue) but because you only used the FY2016 as a reference, FY2017 and FY2018 will not be accounted for. Is there a way to search through multiple sheets or sources and include all the result content?